High speed printer including changeable code means

ABSTRACT

There is disclosed a printer having a moving print symbol carrier with a plurality of print symbols, print hammer means selectively cooperable with the print symbols, a memory in the form of a code wheel, a reader for reading the memory, and a comparator for controlling initiation of operation of the print hammer means in response to a received signal when the print symbol carrier is in the proper position as determinted by the reader, the code wheel having one set of code elements corresponding to each print symbol, two sets of code elements being interchangeable.

United States Patent Guzak, Jr.

[54] HIGH SPEED PRINTER INCLUDING CHANGEABLE CODE MEANS [72] Inventor: John Guzak, Jr., Arlington Heights, 111.

[73] Assignee: SCM Corporation, New York, NY.

[22] Filed: Feb. 17, 1969 [21] Appl. No.: 799,815

[52] U.S.Cl. .l01/93 C, 340/358 [51] Int. Cl. ...B41j 7/54, G080 9/06 [58] Field ofSearch ..235/61.12; 101/93 RC; 340/358, 340/365,172.1,172.5

[56] References Cited UNITED STATES PATENTS 2,015,323 9/1935 Singer et a1. 340/358 1,684,394 9/1928 Haase 235/61 12 2,207,379 7/1940 Korber 235/61.12 X

2,217,342 10/1940 Ladrach ..209/72 2,244,231 6/1941 Armbruster 235/6112 5L; L momma JUEMJM] :isssssa iinnmiim w 3 EBBIE "THEE 25! July4,l972

2,980,772 4/1961 Doberstein ..200/33 3,158,090 11/1964 Hasserman 101/93 RC 3,343,131 9/1967 Bloom et a1 ..101/93 RC X 3,343,481 9/1967 Giannuzzi et al. ..l0l/93 RC 3,366,045 1/1968 Canarutto ..10l/93 RC Primary Examiner-William B. Penn Assistant ExaminerE. M. Coven Att0rneyMason, Kolehmainen, Rathburn & Wyss [57] ABSTRACT There is disclosed a printer having a moving print symbol carrier with a plurality of print symbols, print hammer means selectively cooperable with the print symbols, a memory in the form of a code wheel, a reader for reading the memory, and a comparator for controlling initiation of operation of the print hammer means in response to a received signal when the print symbol carrier is in the proper position as determinted by the reader, the code wheel having one set of code elements corresponding to each print symbol, two sets of code elements being interchangeable.

2 Claims, 6 Drawing Figures P'A'IENTEnJuL 4 mm 3.673.957

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HIGH SPEED PRINTER INCLUDING CHANGEABLE CODE MEANS FIELD OF THE INVENTION This invention relates to the art of selective printing.

BACKGROUND OF THE INVENTION In general, in selective printers having a moving print symbol carrier and a cooperating print hammer, a symbol corresponding to the received signal is printed on a record medium because the print hammer cooperates with the selected print symbol on the print symbol carrier when the print sym bol carrier is in the proper position. If the print symbol carrier moves continuously, operation of the print hammer can commence following a finding of comparison between the received symbol signal and a positional signal from a reader which continuously reads the position of the print symbol carrler.

SUMMARY OF THE INVENTION The present invention uses a memory which has a set of code elements which are directly relates to the print symbols on a continuously moving print symbol carrier. One or more sets of code elements are changeable so that the symbol which is printed is a symbol other than the symbol represented by the received symbol signal. In particular, it is desired to interchange two sets of code elements of the memory so that in response to a received signal corresponding to one of the two sets of code elements printing of a symbol corresponding to the other set of code elements is effected, and vice versa.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a logic diagram illustrating an arrangement of components with which the subject invention is useable;

FIG. 2 is an elevational view, partly in section, showing a fragmentary portion of a print drum, a code wheel, and a clock wheel secured to a common shaft, read heads cooperatively arranged with respect to the code wheel and the clock wheel, and shutters for the code wheel;

FIG. 3 is a side elevational view showing a fragmentary portion of the clock wheel and portions of the shutters on the code wheel;

FIG. 4 is side elevational view showing fragmentary portions of the code wheel and the clock wheel in relation to read heads and a light source;

FIG. 5 is a fragmentary sectional view taken through the code wheel, the clock wheel and one of the shutters; and

FIG. 6 is a portion of a chart indicating Baudot code signals, and corresponding letters and figures symbols.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring to FIG. 1, there is shown a printer having a print symbol carrier in the form of print drum 10. The drum 10 is illustrated as having a plurality of rows of print symbols l2 arranged about its circumference. If desired, a typewheel having a single row of print symbols can be used in carrying out the invention. On the other hand, a print symbol carrier in the form of an endless belt or chain which carries one or more rows of print symbols can be used.

The print symbols 12 on the drum 10 are in alignment with the print symbols of every other row. Thus, lines of similar symbols extend lengthwise of the drum as shown in FIG. 2. Each row has a variety of different print symbols 12. For ex ample, each row can have symbols such as letters of the alphabet commonly referred to as Letters, and symbols which are not letters of the alphabet such as an apostrophe a comma a bell symbol (Q), and so on, commonly referred to as Figures. In the illustrated embodiment, each row has 64 print symbols 12. The print symbols, and their relative locations in each row are the same. When using a five-bit code, such as Baudot Code, a maximum of 32 symbols can be represented by using various combinations of mark and space bits. By adding one additional bit, the maximum number of symbols which can be represented by various combinations of these bits is 64. Thus, by transmitting a Letters signal on a figures signal ahead of the symbol signal, not only can all the letters of the English alphabet be printed, but a considerable number of figures can also be printed. Signals in serial form from a suitable source are converted to parallel signals by a serial-to-parallel converter 14. The position of the drum 10 is constantly read by a reader 16 which reads a memory 28. Received symbol signals from converter 14 and drum position signals as determined by the reader 16 are applied to a comparator 18. The comparator l8 compares these signals, and when comparison exists, it causes print hammer operating circuit 20 to operate print hammer 22. Thus, the print hammer 22 cooperates with the selected print symbol 12 on the continuously rotating drum 10; the symbol is printed on a record medium (not shown) disposed between the print drum l0 and the print hammer 22. The print hammer 22 can be mounted on a travelling carriage (not shown) which can move lengthwise with respect to the print drum 10. If desired, a whole bank of hammers corresponding in number to the number of rows of print symbols can be used to print on the page record medium.

Referring to FIGS. 2 through 5, the reader 16 is shown to include six read heads, specifically light sensing members 24, mounted on a support 26. The memory 28 is shown to include a code wheel 30. The sensing members 24 are in alignment with six rows of code elements, specifically holes 32. The code wheel 30 comprises an opaque circular band 34 in which the code holes 32 are formed and a radial disk or plate 36 joining an edge of the band 34. The code wheel 30 is secured to the same shaft 38 as the print drum 10, and in this way the rotation of the code wheel 30 is synchronized with the rotation of the print drum 10. The shaft 38 is rotatably mounted in the printer frame 39. There are 62 sets of holes 32 and two sets of holes 31 in the code wheel 30. Each set of holes 31 and 32 is in alignment with a corresponding line of print symbols 12 of the print drum 10. Letters are distinguished from figures in that for each letter there is a hole 32 in the sixth position on the code wheel 30, whereas for each figure there is no hole in the sixth position on the code wheel.

The reader 16 includes a pair of light emitters 40 which direct light at a lens 42. The lens 42 concentrates the light into a narrow band approximately as wide as one of the holes 32 and at least as long as the extent of the six holes 32.

The figures symbol, apostrophe is not formed by the code wheel 30 itself, but rather is formed by a separate shutter in the form of a removable clip 44 which has holes 44a, 44b, and 44c in the first, second and fourth positions and no holes in the third, fifth and sixth positions. In like manner, the figures symbol, bell (A), is not formed by the code wheel 30 itself, but rather is formed by a separate shutter in the form of a removable clip 46 which has holes 46a and 46b in the first and third positions and no holes in the second, fourth, fifth and sixth positions. The set of code holes formed on each clip 44 and 46 is read by the sensing members 24 in the same manner as the holes which are formed directly in the band 34 are read by the sensing members 24.

It is apparent the clips 44 and 46 can be interchanged. In interchanging the clips 44 and 46, they are simply removed from the code wheel 30 and the clip 44 is snapped into the position which was previously occupied by the clip 46 and the clip 46 is snapped into the position which was previously occupied by the clip 44. Thus, in response to an incoming figures symbol signal, apostrophe the reader 16 will cause the comparator 18 to find comparison when the print drum 10 is in the position in which the figures symbol bell (A) is in position to be printed, and thus the print hammer 22 will be actuated to print the figures symbol, bell (Q), on the record medium. In like manner, in response to an incoming figures symbol signal, bell (A), the reader 16 will cause the comparator 18 to find comparison when the print drum 10 is in the position in which the figures symbol, apostrophe is in position to be printed, and

thus the print hammer 22 will be actuated to print the symbol, apostrophe on the record medium.

Thus, the printer can be made to print the desired symbol on the record medium, even though the received signal corresponds to a different symbol. By means of the code clips 44 and 46, this can be accomplished without completely changing code wheel 30. In addition, if a particular symbol is not to be printed at all, a clip (not shown) having no holes can be used.

The clips 44 and 46 are identical in construction other than the fact that each has a different set of code holes. Holes 31 in the code wheel 30 permit light to pass through each code hole of the clips 44 and 46. The circular band 34 of the code wheel 30 has two notches 48 and 50 in one edge. These notches 48 and 50 are just wide enough so that the respective clips 44 and 46 cannot shift. Margins ends 52 and S4 of the clips 44 and 46 are hook-shaped in that they wrap around the band 34. The disk or disk portion 36 of the code wheel 30 has two apertures 56 and 58. The other marginal ends of the clips 44 and 46 are bent at approximately right angles to provide locking projections 60 and 62 which enter the respective apertures 56 and 58. The clips 44 and 46 conform to the outer surface of the code wheel 30' The resilient clips 44 and 46 are composed of spring steel and are bent so that their locking projections 60 and 62 will be urged into respective apertures 56 and 58 by spring action. The clips 44 and 46 are releasably locked to the rotatable code wheel 30 and yet can be readily removed by urging their projections 60 and 62 out of the respective apertures 56 and 58 by means of a tool such as a small screwdriver.

A clockwheel 64, having 64 sets of ferromagnetic clock elements 66 corresponding to the 64 sets of code elements or holes in the memory 2% is adjustably secured to the code wheel 36 by screws 65 received in arcuate slots 67. A read head 68 senses each of the clock elements 66 as the clockwheel 64, the code wheel 30, and the print drum 10 rotate as a unit. An access hole 70 in the clockwheel 64 enables the clips 44 and 46 to be snapped onto and removed from the code wheel 30.

Other embodiments and modifications of this invention will suggest themselves to those skilled in the art, and all such of these as come within the spirit of this invention as included within its scope as best defined by the appended claims.

I claim:

ll. A printer including a carrier having a plurality of print symbols thereon; a code wheel having a plurality of code sets permanently defined thereon, at least one set corresponding to a print symbol on said carrier and including at least one code hole in said wheel; and code alteration means detachably mounted on said wheel in juxtaposition to said one code set for covering said hole to alter the relation between said one code set and the print symbol corresponding thereto on said carrier, said code alteration means comprising resilient spring clip means having a deflectable retaining means, said code wheel including means for receiving said retaining means for detachably locking said clip means in position on said wheel.

2. The printer of claim 1 wherein said code wheel includes a surface having a recess defined therein adjacent said one code hole for receiving at least a portion of said spring clip means. 

1. A printer including a carrier having a plurality of print symbols thereon; a code wheel having a plurality of code sets permanently defined thereon, at least one set corresponding to a print symbol on said carrier and including at least one code hole in said wheel; and code alteration means detachably mounted on said wheel in juxtaposition to said one code set for covering said hole to alter the relation between said one code set and the print symbol corresponding thereto on said carrier, said code alteration means comprising resilient spring clip means having a deflectable retaining means, said code wheel including means for receiving said retaining means for detachably locking said clip means in position on said wheel.
 2. The printer of claim 1 wherein said code wheel includes a surface having a recess defined therein adjacent said one code hole for receiving at least a portion of said spring clip means. 